SOUTH WALES' attempts to become a booming European region are being hampered by its outdated motorway, one of Wales' top transport experts warned yesterday.

While Cardiff has turned itself into a European capital it is living on borrowed time because of chronic under-investment in roads and railways, according to Professor Garel Rhys of Cardiff University.

But an environmental group, while agreeing that there had been under-investment in transport, recommended that money should be spent on the railways, not necessarily roads.

Professor Rhys said one of the biggest problems facing South Wales as a whole is the sub-standard M4, which was built in piecemeal sections.

He also warned the South-West will suffer unless a new section of the M4 is built around Port Talbot - possibly with a tunnel beneath the houses.

"We don't have much motorway in Wales," said Prof Rhys, director of the Centre for Automotive Industry Research. "We have less than any other industrial area in the UK.

"All we have is this one artery and frankly it's not up to the job. The Welsh economy has outgrown the road.

"The M4 is not really a coherent major trunk route from the Severn Bridge down to Pont Abraham."

One of the main problems was that several sections had just two lanes for traffic in each direction - north of Newport, north of Cardiff and west of Margam.

According to AA statistics an average of 85,000 motorists use the M4 around the Cardiff junctions 32/33 every day with perhaps 70,000-75,000 hitting the motorway on the Neath, Port Talbot and Swansea sections daily.

"You don't see many two-lane motorways in England now. They've been widened because of the needs of the economy to have a better transport system.

"Cardiff is beginning to be a proper capital in the sense of generating so much economic activity. It's generating jobs for people further and further away from it.

"The reason traffic on the M4 comes to a stop is the new housing estates in Bridgend, where housing is cheaper. People are also commuting to Cardiff from the Valleys."

But he warned that Cardiff's growth could be slowed without major investment in the main roads and railways - and the authorities were simply hoping something would turn up.

"In fact, something doesn't turn up. About the only pieces of transport investment of any size at the moment are the Heads of the Valleys widening and the Vale of Glamorgan rail scheme."

A new section of the M4 to bypass the narrow Brynglas tunnels, north of Newport, has been under consideration for more than a decade. CBI Wales and trade unions recently called for urgent moves to build the new road, at a cost of about #350m.

Prof Rhys warned that the Port Talbot bottleneck - where the M4 uses a bypass built in the 1960s - would constrain economic growth in Swansea and West Wales.

"When it was built as the A48(M) it had a 50mph limit. It has a very poor corner. Now we have vehicles with completely different characteristics."

He admitted the cost of a new motorway around Port Talbot would be high but said the economy would suffer if the problem was ignored.

The problem, now and in the 1960s, is that the narrow strip of low land between the hills and the sea is occupied by Port Talbot and its steelworks.

However, some industries in the area have diminished or disappeared and Prof Rhys suggested a coastal route might be an option in the long term.

Another possibility was a "cut and fill" tunnel under the houses at Port Talbot.

"Looking at the total economic needs of West Wales, this might be the price that has to be paid," said Prof Rhys.

The main railway line in South Wales had been neglected for decades. When the InterCity 125s were introduced in the 1970s the major speed increases were between Bristol Parkway and Reading, he said. Other major industrial areas had more comprehensive motorways and local roads, and many also had tram systems or electric railways.

"If you look at the motorway and upgraded railway lines per square mile, Wales comes out near the bottom of the UK.

"Our entire transport infrastructure has been left behind by the growth we've experienced. All too often Wales seems to be satisfied with second-rate or third-rate transport infrastructure. If the economy continues to outgrow the transport system, are we going to reduce the economy? Of course not, because that will cost jobs.

"The amount of money we've spent per square mile in Wales since the war means we have a lot of catching up to do, let alone getting ahead."

Neil Crumpton, transport campaigner for Friends of the Earth Cymru, said he agreed that too little had been invested in Welsh transport but said new motorways could damage the economy, by generating more traffic and enabling more services to be provided in Wales by companies based far away.

He said there was a case for widening two-lane sections of the M4 to three lanes if it could be done fairly cheaply but the rail network should be the priority for investment.

"Whatever you think about the state of the roads in South Wales, the railways need more attention. The Cardiff-Swan-sea train service was cut back in the late 1990s, when there were policies to increase rail travel."

He said improving that service would reduce the number of cars on the M4 and would cost far less than a new road around Port Talbot, where #55m had been earmarked just for a short new local road.

Mistakes we make

SPOILING the ship for a ha'porth of tar seems to have been the guiding principle behind parts of Wales' main highways.

The original Severn Bridge was left needing frequent repairs.

And the engineers did not allow for the strong winds which could affect such an exposed road, with the result that the bridge was closed in high winds and many caravans and lorries were toppled over.

In the 1990s the same mistake was made again, with the Briton Ferry viaduct. And by the time the bridge was built, there was no need for it to have been so elevated anyway - ships no longer used the river beneath.

Many motorists in North Wales believe twin tunnels should have been bored through the headlands either side of Penmaenmawr, where the A55 has new tunnels for the westbound carriageway only. Eastbound traffic winds around the coast on roads built in the 1930s. Failure to strengthen the parapet walls on one of the old roads when the A55 was being built led to a two-year emergency rebuilding scheme, finished last month, which caused long tailbacks.